An electric toothbrush is ordinarily shown in FIG. 1, including a handle 1 and a brush head, wherein a motor 3 is arranged in the handle 1, a transmission rod is arranged in the brush head, a motor is provided with a rotating shaft 32, the rotating shaft extends from the casing 31 of the motor, a transmission connection member 4 is arranged between the transmission rod and the rotating shaft 32 of the motor, the transmission connection member 4 is used for connecting the rotating shaft 32 extending from the casing of the motor with the transmission rod, and the rotating shaft 32 transmits power to the transmission rod through the transmission connection member 4 to drive the transmission rod to move and further drive the brush head to do a movement of cleaning teeth; a conventional sealing member 5′ is arranged at a rotating shaft extending position of the outer surface of the casing 31, and the conventional sealing member 5′ is arranged around the rotating shaft 32 of the motor to seal the casing 31 of the motor and prevent damage of the motor 3 caused by water and other pollutants which are generated when teeth are brushed and enter the inside of the casing of the motor; in order to improve the effect of sealing, the sealing member remains a cavity 51′ between the rotating shaft and the casing, and the cavity 51′ is filled with sealing oil, so that the sealing effect of the sealing member is better.
The prior art has the disadvantages that the sealing member is fixed by the handle and keeps static sealing connection with the casing of the motor, the sealing member and the rotating shaft are in rotary sealing connection, when the teeth are brushed, a powdered material of toothpaste generates an abrasion effect on a seal fitting position of the sealing member and the rotating shaft, and accordingly, leakage is easily caused after the toothbrush is used for a long time, water and other corrosive materials enter the motor from the seal fitting position to damage the motor.
Information disclosed under the background section is only for enhancement of understanding of the general background of the present invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.